The present invention relates to a film scanner for scanning images formed on a silver-salt film.
Recently, as personal computers become more widespread, image data is processed using the personal computer and recorded. It has been desired that the images formed on the silver-salt film are converted to electronic images (i.e., the image data) so as to be processed in the personal computers. For this purpose, a film scanner for capturing the images on the silver-salt films has been developed and used. With the film scanner, the optical images on the film are read and converted into the image data. Generally, the film scanner is provided with a CCD line sensor. By scanning the image in a direction (i.e., a main scanning direction) in which the CCD line sensor extends, while the film is moved relative to the CCD line sensor in a direction (i.e., an auxiliary scanning direction) perpendicular to the main scanning direction, a two-dimensional area is scanned.
In such a film scanner, it is preferable that not only 35 mm film but a various type of films having various sizes can be scanned. However, in order to scan the various size of images using a CCD having a fixed size, a magnification of an imaging lens for forming the image of a picture (i.e., an image on the film) on the CCD should be changed. For varying the magnification, a scanner in which a plurality of imaging lens having different focal lengths which can be selectively utilized, or a scanner provided with a zoom lens have been suggested.
Further to the above, for films having different sizes, aspect ratios of the images are different, and thus, moving amounts for the auxiliary scanning should be varied depending on the film size. A scanner in which the moving amount of the auxiliary scanning is varied has also been developed.
As described above, with the conventional film scanner, by setting the scanning conditions (i.e., the focal length of the imaging lens, the moving amount in the auxiliary scanning direction, etc.), different types of films can be scanned. In the conventional scanners, however, as described above, the size and type of the film to be scanned is first recognized by an operator. Then, the operator manually sets the scanning conditions for the film to be scanned.
If a plurality of films having different sizes are to be frequently replaced and scanned, the operator is required to adjust the conditions every time the films are exchanged, which is extremely troublesome. Further, if the operator fails to set the condition or set the condition for a different film, the images on the film may not be scanned correctly.
The above problem also occurs if a various type of films such as infrared film and X-ray film are to be scanned, or a various type of images such as negative images, positive images, color images having different gamma characteristics are to be scanned. In such a case, even if the size of the image is the same, the scanner should execute an image processing operation suitable for the original image. In such a case, according to the conventional scanner, the type of the image to be scanned should be recognized by the operator, and then the scanning condition should be adjusted by the operator manually.
It is therefore an object of the invention to provide an improved film scanner in which, when films to be scanned are exchanged, the scanning condition is automatically adjusted.
For the object, according to the invention, there is provided a film scanner for scanning images formed on a film, which is provided with a film type identifying system that automatically identifies a type of a film to be scanned and a scanning condition setting system that automatically sets a scanning condition in accordance with the type of film identified by the film type identifying system.
Since the film type is automatically identified, and the scanning condition is set accordingly, the scanning operation can be performed easily even if films of different types are frequently exchanged.
In particular, the film type identifying system identifies films having different sizes. In this case, the film type identifying system identifies at least 8 mm film, 16 mm film, 35 mm film and xe2x80x9cbrowniexe2x80x9d type film. Alternatively or optionally, the film type identifying system identifies films having different gamma characteristics. In this case, the image processing operation is varied in accordance with the gamma characteristics. Further optionally or alternatively, the film type identifying system identifies at least negative film, positive film, infrared film and X-ray film. Also in this case, image processing operation may be changed in accordance with the identified film type.
Optionally, the film scanner may be provided with a line image sensor unit for scanning the film in a main scanning direction and an auxiliary scanning system that moves the film relative to the line image sensor in an auxiliary scanning direction which is perpendicular to the main scanning direction. In this case, the film type identifying system identifies films having different sizes, and the scanning condition setting system sets a focal length of an imaging lens that forms an image of the film on the line image sensor.
In such a case, the image condition setting system includes a switching mechanism that locates one of a plurality of imaging lenses corresponding to the film to be scanned. Alternatively, a zoom lens system may be employed and the focal length thereof may be varied without moving the position of the lens.
If various sizes of films are to be scanned, the scanning condition setting system sets a moving amount of the film relative to the line image sensor for scanning each frame of image in accordance with the size of the film to be scanned.
Optionally, the film identifying system identifies the films by recognizing film holders holding the films, different films being held by different film holders.
In one case, the film identifying system optically identifies the film holder. This represents an example of a non-contact detection system, and other kinds of non-contact detection systems may be employed.
In particular, the film identifying system may include a plurality of openings forming unique patterns for respective film holders, the plurality of openings being formed on the respective film holders and a detecting system that detects the pattern formed on the film holder.
It is preferable, in such a case, that an image sensor that is used for scanning the film can be used for the detecting system.
Still optionally, the film identifying system includes a code indication member provided on each of the film holders, the code indication member carrying a code indicating the film held by each film holder and a code detector that detects the code indicated by the code indication member. In a particular case, the code indication member may carry a bar code.